The RING network: improvements to a GPS velocity field in the central Mediterranean

Since 2004, a continuous Global Positioning System (GPS) network has been
operated by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) to
investigate active tectonic processes in Italy and the surrounding regions,
which are still largely debated. This important infrastructure is known as
Rete Integrata Nazionale GPS (RING) network, and it consists of about 130
stations that are deployed all over Italy. The development and realization of
a stable GPS monumentation, its integration with seismological instruments,
and the choice of both satellite and internet data transmission, make this
network one of the most innovative and reliable CGPS networks in the
world. The technologically advanced development of the RING network has
been accompanied by the development of different data processing strategies,
which are mainly dependent on the use of different GPS analysis software.
The different software-related solutions are here compared at different scales
for this large network, and the consistency is evaluated and quantified within
an RMS value of 0.3 mm/yr.

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